Speed-indicator.



No. 843,361. PATBNTED FEB. 5, 1907.

W. G. PLANK. SPEED INDICATOR. APPLICATION FILED AUG.1, 1906.

W/ TNESSES PATENT OFFTGE.

T/VILL'IAM CHARLES PLANK, OF LAS FLORES, MEXTO.

SPEED-INDHCATOR.

Specification of Letters Patent.

Patented Feb. 5, 190'?.

Application led August 1,1906. Serial No. 328.731.

To all whom t may concern.-

ence, in which is engaged the end of a set- Be it known that I, VILLIAMCHARLES i screw 15, threaded transversely through the PLANK, a citizenof the United States, and a resident of Las Flores, B. C., Mexico, haveinvented anew and Improved Speed-Indicator, of which the following is afull, clear, and'exact description.

This invention is an improvement in speedindicators, designed tofacilitate the taking of the speed of rotating shafts.

Considerable dilliculty has been heretofore experienced inftaking thespeed of shafts with indicators of ordinary construction, due to thefact that the spindle of the indicator could not be engaged with theshaft-center at the exact moment the seconds-hand of a watch employed intiming Aits application registers with a seconds-mark on the watchdial.This dilliculty is more pronounced in using an indicator in closequarters and on high-speed shafts with small center-marks, oftenrequiring a resetting of the indicator when used under such conditions.

The object of my invention is to overcome this dilliculty by producingan indicator in which there will be no danger of the spindlecommunicating its movement to the indicator-dial until such time asdesired by the user. This is accomplished by making the spindle in twosections, which are adapted to be automatically connected by pressingthe indicator forward.

The ligure of the drawing represents one embodiment of my invention,partly in section, forming a part of this specification, and on whichlike reference characters are used to designate the same part in thedescription.

The numeral 1 indicates the body portion of the indicator, having ahandle 2 and a circular offset box 3 at one side thereof, provid.- ing achamber 4, leading into a longitudinal bore 5 at the forward end of theindicator. Journaled in the chamber 4 is a worm-wheel 6, made fast to anindicator-disk 7, carrying the zero-mark, and having usually the samenumber of teeth 9 as there are 0raduaticns on a dial 10, each tooth andgraduation ccrresponding to one revolution of the shaft, one hundredteeth and graduaticns being indicated in the present case.

Intermeshing with the worin-gear 6 is a worm 11, jcurnaled in a recessin the rear end of the bore 5 by means of a reduced end 12 and at itsopposite end fitting the bere by an enlargement 13, said enlargement 13having a groove 14 passing about the circumferbody 1, thereby preventingany longitudinal movement of the worin 11. The enlargenient 13constitutes a section of the divided spindle referred to, the othersection 16 of which is conical at each end, as at 17 and 18, and adaptedto slide in the outer end of the bore 5. The conical end 17 is designedto engage the opposed end of the section or enlargement 13, which is anexact counterpart of it, and lined with a rubber center 19, in orderthat when the sections are engaged the l'rictional contact will besuflicient to positively drive the worin 11 and wormwheel 6 asthespindle 16 rotates.

For holding the conical end 17 'in andout of engagement with ythe rubbercenter 19 is a pin 20,' spring-pressed by a ilat spring 21, said pintransversely entering the bore 5 and suitably adapted to engage eitherof the circumferential grooves 22 in the section 16.

ln the operation of the indicator the parts are in the relationrepresented in the drawing, wherein the Zero-marks of the disk 7 anddial 10` are in register. Vith the parts in this relation the section 16of the spindle is free to turn without influencing the remainder of themechanism. Vhen the conical end 1S is engaged with the center of arotating shaft and the seconds-hand of a watch held by the operator isat the desired point, the handle 2 is instantly pressed forward, pushingthe section 16 of the spindle inwardly, which automatically releases thepin 2O in a well-known manner from the rear groove 22 and projects itinto the groove adjacent. This forcibly contacts the conical end 17 withthe rubber center 1Q, transmitting the rotation of the section 16 of thespindle to the worm and worm-wheel, and there by indicates therevolutions of the shaft in any given time.

It is evident that various changes may be made in the details ofconstruction hereinbefore described without departing from the essentialcharacteristics of this invention, and T consider that T am entitled tosuch modifications as fall within the scope of the invention as claimed.

Having thus described my invention, I claim as new and desire to secureby Letters Patent- 1. Tn a speed-indicator, a circular box projecting atone side thereof, a worin-wheel journaled in the box, a longitudinalbore IOO leading into the boX, a worm meshing with the worm-wheel andjournaled in the bore, an enlargement at one end of the worm,constituting a section of the indicator-spindle, a set screw passinginto a circumferential groove of said section to prevent thelongitudinal movement thereof, an outer section of the spindle freelyrotatable independently of the worm, a spring-pressed pin entering acircumferential groove of the outer section to hold the sectionsdisengaged, and a second adjacent circumferential groove in the outersection adapted to be engaged by said pin to hold the sections together.

2. In a speed-indicator, a spindle made of two sections, a worm-wheelcarried by one section, means for holding the worm-wheel againstlongitudinal movement, means for holding the sections disengaged, arubber center interposed between said sections, and means for holdingthe sections in contact with the rubber center when pushed together.

3. In a speed-indicator, a spindle made in two sections, means forpreventing the longitudinal movement of one section, a second sectionadapted to be engaged therewith having conical ends, a circumferentialgroove passing about said second section, a springpressed pin forengaging said groove to hold the sections apart, and an adjacentcircumferential groove in said second section for engagement with saidspring-pressed pin to hold the sections together.

4;. In a speed-indicator, a spindle made in two sections, means forpreventing the longitudinal movement of one of said sections, a rubbercenter carried by one of said sections, a second section conical at eachend, circumferential grooves passing about said second section, aspring-pressed pin entering one of said grooves for holding the sectionsapart, andmeans whereby when the sections are pressed together thespring-pressed pin enters the other of said grooves and holds thesections frictionally engaged to the intermediate rubber center.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

WILLIAM CHARLES PLANK.

Witnesses:

ANNA J'. JEFFREY, E. J. HOLLAND.

